These are the perfect sights for your Glock MOS with Vortex Venom red dot. They co-witness perfectly. I chose the all black over the fiber optic front to reduce the opportunity for confusion of 2 dots. Despite being skeptical about the all black sights, I am very happy with them and they are working out great as back up sights. I installed the sights on a Glock 17 Gen 5 MOS and they are perfect. You will have to file down the rear sight a bit, but you will get a great fit when you are done. Best option for back ups to your Venom.